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<div class="titlepage"><div><div><h3 class="title">
<a name="fusion.extension.sequence_facade"></a><a class="link" href="sequence_facade.html" title="Sequence Facade">Sequence Facade</a>
</h3></div></div></div>
<h5>
<a name="fusion.extension.sequence_facade.h0"></a>
        <span class="phrase"><a name="fusion.extension.sequence_facade.description"></a></span><a class="link" href="sequence_facade.html#fusion.extension.sequence_facade.description">Description</a>
      </h5>
<p>
        The <a class="link" href="sequence_facade.html" title="Sequence Facade"><code class="computeroutput"><span class="identifier">sequence_facade</span></code></a>
        template provides an intrusive mechanism for producing a conforming Fusion
        sequence.
      </p>
<h5>
<a name="fusion.extension.sequence_facade.h1"></a>
        <span class="phrase"><a name="fusion.extension.sequence_facade.synopsis"></a></span><a class="link" href="sequence_facade.html#fusion.extension.sequence_facade.synopsis">Synopsis</a>
      </h5>
<pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span><span class="keyword">typename</span> <span class="identifier">Derived</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">TravesalTag</span><span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">IsView</span> <span class="special">=</span> <span class="identifier">mpl</span><span class="special">::</span><span class="identifier">false_</span><span class="special">&gt;</span>
<span class="keyword">struct</span> <span class="identifier">sequence_facade</span><span class="special">;</span>
</pre>
<h5>
<a name="fusion.extension.sequence_facade.h2"></a>
        <span class="phrase"><a name="fusion.extension.sequence_facade.usage"></a></span><a class="link" href="sequence_facade.html#fusion.extension.sequence_facade.usage">Usage</a>
      </h5>
<p>
        The user of <a class="link" href="sequence_facade.html" title="Sequence Facade"><code class="computeroutput"><span class="identifier">sequence_facade</span></code></a> derives his sequence
        type from a specialization of <a class="link" href="sequence_facade.html" title="Sequence Facade"><code class="computeroutput"><span class="identifier">sequence_facade</span></code></a> and passes the derived
        sequence type as the first template parameter. The second template parameter
        should be the traversal category of the sequence being implemented. The 3rd
        parameter should be set to <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">true_</span></code>
        if the sequence is a view.
      </p>
<p>
        The user must implement the key expressions required by their sequence type.
      </p>
<div class="table">
<a name="fusion.extension.sequence_facade.t0"></a><p class="title"><b>Table 1.106. Parameters</b></p>
<div class="table-contents"><table class="table" summary="Parameters">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  Name
                </p>
              </th>
<th>
                <p>
                  Description
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span></code>, <code class="computeroutput"><span class="identifier">Seq</span></code>
                </p>
              </td>
<td>
                <p>
                  A type derived from <a class="link" href="sequence_facade.html" title="Sequence Facade"><code class="computeroutput"><span class="identifier">sequence_facade</span></code></a>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">N</span></code>
                </p>
              </td>
<td>
                <p>
                  An <a href="http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL
                  Integral Constant</a>
                </p>
              </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break"><div class="table">
<a name="fusion.extension.sequence_facade.t1"></a><p class="title"><b>Table 1.107. Key Expressions</b></p>
<div class="table-contents"><table class="table" summary="Key Expressions">
<colgroup>
<col>
<col>
</colgroup>
<thead><tr>
<th>
                <p>
                  Expression
                </p>
              </th>
<th>
                <p>
                  Result
                </p>
              </th>
</tr></thead>
<tbody>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">begin</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                </p>
              </td>
<td>
                <p>
                  The type of an iterator to the beginning of a sequence of type
                  <code class="computeroutput"><span class="identifier">Seq</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">begin</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">&gt;::</span><span class="identifier">call</span><span class="special">(</span><span class="identifier">seq</span><span class="special">)</span></code>
                </p>
              </td>
<td>
                <p>
                  An iterator to the beginning of sequence <code class="computeroutput"><span class="identifier">seq</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">end</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                </p>
              </td>
<td>
                <p>
                  The type of an iterator to the end of a sequence of type <code class="computeroutput"><span class="identifier">Seq</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">end</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">&gt;::</span><span class="identifier">call</span><span class="special">(</span><span class="identifier">seq</span><span class="special">)</span></code>
                </p>
              </td>
<td>
                <p>
                  An iterator to the end of sequence <code class="computeroutput"><span class="identifier">seq</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">size</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                </p>
              </td>
<td>
                <p>
                  The size of a sequence of type <code class="computeroutput"><span class="identifier">Seq</span></code>
                  as an <a href="http://www.boost.org/libs/mpl/doc/refmanual/integral-constant.html" target="_top">MPL
                  Integral Constant</a>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">size</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">&gt;::</span><span class="identifier">call</span><span class="special">(</span><span class="identifier">seq</span><span class="special">)</span></code>
                </p>
              </td>
<td>
                <p>
                  The size of sequence <code class="computeroutput"><span class="identifier">seq</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">empty</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                </p>
              </td>
<td>
                <p>
                  Returns <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">true_</span></code> if <code class="computeroutput"><span class="identifier">Seq</span></code>
                  has zero elements, <code class="computeroutput"><span class="identifier">mpl</span><span class="special">::</span><span class="identifier">false_</span></code>
                  otherwise.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">empty</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">&gt;::</span><span class="identifier">call</span></code>
                </p>
              </td>
<td>
                <p>
                  Returns a type convertible to <code class="computeroutput"><span class="keyword">bool</span></code>
                  that evaluates to true if the sequence is empty, else, evaluates
                  to false.
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">at</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">,</span> <span class="identifier">N</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                </p>
              </td>
<td>
                <p>
                  The type of element <code class="computeroutput"><span class="identifier">N</span></code>
                  in a sequence of type <code class="computeroutput"><span class="identifier">Seq</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">at</span><span class="special">&lt;</span><span class="identifier">Seq</span><span class="special">,</span> <span class="identifier">N</span><span class="special">&gt;::</span><span class="identifier">call</span><span class="special">(</span><span class="identifier">seq</span><span class="special">)</span></code>
                </p>
              </td>
<td>
                <p>
                  Element <code class="computeroutput"><span class="identifier">N</span></code> in sequence
                  <code class="computeroutput"><span class="identifier">seq</span></code>
                </p>
              </td>
</tr>
<tr>
<td>
                <p>
                  <code class="computeroutput"><span class="identifier">sequence</span><span class="special">::</span><span class="keyword">template</span> <span class="identifier">value_at</span><span class="special">&lt;</span><span class="identifier">Sequence</span><span class="special">,</span> <span class="identifier">N</span><span class="special">&gt;::</span><span class="identifier">type</span></code>
                </p>
              </td>
<td>
                <p>
                  The type of the <code class="computeroutput"><span class="identifier">N</span></code>th
                  element in a sequence of type <code class="computeroutput"><span class="identifier">Seq</span></code>
                </p>
              </td>
</tr>
</tbody>
</table></div>
</div>
<br class="table-break"><h5>
<a name="fusion.extension.sequence_facade.h3"></a>
        <span class="phrase"><a name="fusion.extension.sequence_facade.include"></a></span><a class="link" href="sequence_facade.html#fusion.extension.sequence_facade.include">Include</a>
      </h5>
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">sequence</span><span class="special">/</span><span class="identifier">sequence_facade</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
<span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">fusion</span><span class="special">/</span><span class="identifier">include</span><span class="special">/</span><span class="identifier">sequence_facade</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
</pre>
<h5>
<a name="fusion.extension.sequence_facade.h4"></a>
        <span class="phrase"><a name="fusion.extension.sequence_facade.example"></a></span><a class="link" href="sequence_facade.html#fusion.extension.sequence_facade.example">Example</a>
      </h5>
<p>
        A full working example using <a class="link" href="sequence_facade.html" title="Sequence Facade"><code class="computeroutput"><span class="identifier">sequence_facade</span></code></a> is provided in triple.cpp
        in the extension examples.
      </p>
</div>
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<td align="right"><div class="copyright-footer">Copyright © 2001-2006, 2011, 2012 Joel de Guzman,
      Dan Marsden, Tobias Schwinger<p>
        Distributed under the Boost Software License, Version 1.0. (See accompanying
        file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
      </p>
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